Using the Source–Victim Matrix to Connect RE102 and RS103 in Shipboard EMC

Introduction

Electromagnetic Compatibility (EMC) is not just about passing tests in the lab. On naval platforms, dozens of communication, radar, and navigation systems must operate side by side without interfering with one another.

Two MIL-STD-461G tests cover opposite sides of this challenge:

• RE102 (Radiated Emissions): how much a device radiates.
• RS103 (Radiated Susceptibility): how much a device can withstand.

Individually, they ensure compliance. Together, they help answer the key question: can these systems coexist in the same shipboard environment?
That’s where the Source–Victim (SV) matrix comes in.

RE102 vs RS103 in Plain Terms

• RE102: You sweep across frequencies and measure a device’s emitted field strength (V/m or dBµV/m).
• RS103: You expose the device to known fields and check that it keeps working up to a defined immunity threshold (V/m or dBµV/m).

On their own, these tests are useful. But by combining them, you get a system-level picture of electromagnetic compatibility.

The SV Matrix Concept

The SV matrix compares every emitter (source) against every receiver (victim):

• Source device: generates the field (e.g., SATCOM, VHF radio, radar).
• Victim device: could be disturbed (e.g., GPS, NAVTEX, navigation radar).
• Distance: separation on the ship.
• Emission at 1 m (RE102): baseline radiated level.
• Emission at victim location: adjusted for distance and coupling.
• RS103 immunity level: the victim’s required tolerance.
• Margin (dB):

  \text{Margin} = RS103 - Emission\_{at\ victim}

• PASS/FAIL: Positive margin = safe. Negative margin = potential interference.

Example from Shipboard Data

From a sample dataset of 338 source–victim pairs, two scenarios stand out:

• Self-coupling (INMARSAT-C → INMARSAT-C)
  • Emission at victim ≈ 13.8 MV/m (262 dBµV/m)
  • RS103 requirement = 50 V/m (154 dBµV/m)
  • Margin = –109 dB → FAIL
  • Interpretation: extreme numbers (likely model placeholders), but it reminds us that self-interference is real.
• INMARSAT-C → NAVTEX
  • Emission at victim ≈ 0.87 V/m (119 dBµV/m)
  • RS103 requirement = 50 V/m (154 dBµV/m)
  • Margin = +35 dB → PASS
  • Interpretation: NAVTEX is well protected from INMARSAT emissions at this distance.

Workflow (Text Diagram)

Source Device (Tx) --> RE102 Emission at 1 m
                      |
                      v
           Propagation / Coupling (distance, shielding)
                      |
                      v
      Predicted Field at Victim (E_at_v, V/m & dBµV/m)
                      |
                      +--> Compare with RS103 Immunity Threshold
                                 |
                                 v
                        Margin = RS103 - E_at_v
                                 |
                       +---------+----------+
                       |                    |
                  PASS (positive)      FAIL (negative)
                       |                    |
              Record in SV Matrix    Apply Mitigation (filter, shield, relocate)

Why It Matters

• Holistic view: Instead of testing devices in isolation, you see how they interact.
• Design guidance: Placement, shielding, or filtering decisions are clearer.
• Early warning: Margins highlight risk areas before integration or deployment.
• Mission reliability: On ships, where space is tight and systems are dense, this method prevents costly surprises.

Example SV Matrix (Text Table)

               |  Source: VHF  |  Source: SATCOM  |  Source: Radar
---------------+----------------+-----------------+----------------
Victim: GPS    |   +28 dB PASS  |   +12 dB PASS   |   -6 dB  FAIL
Victim: NAVTEX |   +35 dB PASS  |   +18 dB PASS   |   +9 dB  WARN
Victim: Radar  |   +42 dB PASS  |   -3 dB  FAIL   |   +5 dB  WARN

• Positive margin = PASS (safe)
• Slightly positive margin = WARN (borderline)
• Negative margin = FAIL (interference risk)

Conclusion

The SV matrix bridges the gap between RE102 (what a system emits) and RS103 (what a system must tolerate). Instead of isolated pass/fail results, you get a system-level compatibility map.

For complex shipboard environments, this method turns EMC analysis from a checkbox exercise into a practical design tool that directly improves mission readiness.